The Ohio Department of Public Health lists Huntington as a bacteria contamination alert, on its BeachGuard website. Veterans Beach in Avon Lake and Lakeview Beach in Lorain have the same status.

The yellow flag warning is posted when the "level of bad bacteria in the water has reached unsafe levels and could make you sick. Children, the elderly and those in ill health or weakened immune systems are advised not to swim," the state says.

Edgewater and Villa Angela have more serious warnings, of a recreational public health advisory. That warning is posted when a harmful algal bloom has been detected. Swimming and wading are not recommended for children, pregnant women, pets and people with certain medical conditions.

The blooms off Cleveland, and in the rest of the central basin, are a different type cyanobacteria that blooms in the western basin," said Justin Chaffin, a senior researcher at Ohio State University's Stone Laboratory in Lake Erie.

"Low biomass blooms are typical for the offshore waters of the central basin in early to mid-July, but they have washed ashore where they can turn a beach or marina very green," he said.

The blooms are usually short-lived, lasting a week or two, Chaffin said.

The Northeast Ohio Regional Sewer District discovered the problem Friday, when testing for cyanobacteria. The sewer district tested the water and found the bacteria anabaena.

The standard is a level 6, and results showed at level 10 at Edgewater and about a level 5 at Villa Angela, NEORSD spokeswoman Jeannie Smith said. The Cuyahoga County Department of Health is awaiting test results for Huntington Beach.

"We are monitoring the situation and based on data from water testing will continue updating signage and guest communications appropriately," Metroparks spokeswoman Jacqueline Gerling wrote in an email Monday.

The beaches remained open throughout the ferociously hot pre-July 4 weekend and are open now, with warnings.

Cleveland Metroparks said they have not received any reports of illnesses from algal blooms.

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